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1.
Capture‐recapture methods relying on dorsal fin natural markings have never been applied successfully to striped dolphins, Stenella coeruleoalba, and were rarely used to assess abundance of short‐beaked common dolphins, Delphinus delphis. We used digital photo‐identification to obtain abundance estimates of striped and common dolphins living in mixed groups in the Gulf of Corinth, Greece. The proportion of either species was calculated based on the relative number of photographs of adult animals showing relevant portions of their body during conspicuous surfacings. Striped dolphins and common dolphins averaged 95.0% and 3.2% of all individuals, respectively. Animals showing intermediate pigmentation accounted for another 1.8%. Striped dolphin numbers were relatively high, with a point estimate of 835 animals (95% CI = 631–1,106). Common dolphins numbers were low (point estimate 28 animals; 95% CI = 11–73) and individuals were scattered within striped dolphin groups, indicating that this common dolphin population may be nonviable. Within a semiclosed Gulf exposed to considerable anthropogenic impact, the future of both dolphin species is of concern due to their suspected geographic isolation and restricted extent of occurrence. Information provided here can be used to inform timely conservation efforts.  相似文献   

2.
Most of our current understanding of rarity has come from studies of terrestrial plants and animals, whereas freshwater habitats remain poorly documented under this topic. Here we considered the spatial distribution patterns of rarity at the river catchment scale, for five freshwater taxa (fish, Ephemeroptera, Plecoptera, Trichoptera and Coleoptera) in southwestern France. The data were collected at 554 and 155 sampling sites for fish and aquatic insects, respectively. General Linear Modelling was used to assess the influence of some typological variables (elevation, stream order, distance from source, and reach slope) on local numbers of rare species (restricted range). The relative numbers of rare species per taxa varied from 16% (Plecoptera) to 59% (Trichoptera). GLM chiefly yielded highly significant correlations between rarity and distance from the source and/or elevation for all taxa, showing that numbers of rare stream species increase towards downstream areas within the stream system. The spatial patterns in rarity for the different study taxa were rather concordant, probably as a result of similar responses to environmental conditions. By focusing on integrative variables, we emphasized the influence of river typology on the rarity of aquatic animals. Areas which carry rare species may concentrate an important fraction of the regional biodiversity. If end-users need geographic models (i.e. maps) to design river management frameworks, numerical patterning is needed to provide theoretical backgrounds: by predicting what the rarity should be like in a given area, we can provide explicit spatial schemes that may be useful to target further research, and to implement management options.  相似文献   

3.
Since late in 2004, brief abstracts of projects licensed under the Animals (Scientific Procedures) Act 1986 have been published on the Home Office website. These are produced by the Project Licence Holders, and their publication is seen by the Home Office as contributing to greater openness and to greater public understanding of the use of animals in science, and how it is regulated. Here, we assess the value of the database for this purpose, based on an examination of the 1400 abstracts published up to January 2008. The abstracts are generally strong on justification, but often very poor at describing the likely effects on the animals used. In many cases, they lack basic information on the procedures applied, and the numbers, and even the species, of animals involved. A significant number of projects lack abstracts altogether. In order to ensure that the database gives a complete and balanced picture of animal use in research, we consider that it should be mandatory to submit an abstract, which should include at least the species and numbers of animals used, the adverse effects they are likely to experience, and the severity limits assigned to the procedures applied to them. The value of the database would also be improved greatly, if it were more readily searchable, at least by species, level of severity, and broad area of research.  相似文献   

4.
Yang  Wenjing  Liu  Dandan  You  Qinghui  Chen  Bin  Jian  Minfei  Hu  Qiwu  Cong  Mingyang  Ma  Keping 《中国科学:生命科学英文版》2021,64(4):584-592
Taxonomic bias is a well-known shortcoming of species occurrence databases. Understanding the causes of taxonomic bias facilitates future biological surveys and addresses current knowledge gaps. Here, we investigate the main drivers of taxonomic bias in occurrence data of angiosperm species in China. We used a database including 5,936,768 records for 28,968 angiosperm species derived from herbarium specimens and literature sources. Generalized additive models(GAMs) were applied to investigate explanatory powers of 17 variables on the variation in record numbers of species. Five explanatory variables were selected for a multi-predictor GAM that explained 69% of the variation in record numbers: plant height, range size, elevational range, numbers of scientific publications and web pages. Range size was the most important predictor in the model and positively correlated with number of records. Morphological and phenological traits and social-economic factors including economic values and conservation status had weak explanatory powers on record numbers of plant species, which differs from the findings in animals, suggesting that causes of taxonomic bias in occurrence databases may vary between taxonomic groups. Our results suggest that future floristic surveys in China should more focus on range-restricted and socially or scientifically less "interesting"species.  相似文献   

5.
Y Tajima 《Jikken dobutsu》1975,24(2):67-77
The movement for modernization of experimental animals in Japan started around 1950. Since that time, a quarter of a century has passed. This article outlines the present status of experimental animals in Japan and makes comparisons with various other countries. Number of animals used: According to three surveys performed in the past (1956, 1960 and 1970), the numbers used of many species are increasing (Table 1). However, it can not be said simply that the numbers are increasing every year. Taking the United States where surveys are performed every year as an example (Table 3), it is evident that the peaks for use of some species are past (the same tendencies were seen in India and Sweden which have conducted more than four surveys in the past (Table 4). The same tendencies would probably also be seen in Japan if surveys were conducted annually. Quality of animals: It is easy to procure genetically and microbiologically controlled rats and mice. However, investigations into the establishment, production and supply of other species of such high quality are insufficient. This situation is almost the same as that in European countries. Miscellaneous: The present status of other items related to experimental animals is as follows: Facilities and equipment: Higher level facilities were first provided in companies, followed by testing and research institutes. At present, medical universities are providing such facilities. Feed: Pellet type diets are widely used for the various species. Care and management: In April, 1974, "The Law for the Protection and Control of Animals" came into force. This law includes regulations concerning animal experimentation but investigations concerning these standards have just begun. Training of technicians and specialists: The Japan Experimental Animal Research Association provides a correspondence course, tests and recognition for technicians. About 10 veterinary colleges have undergraduate or postgraduate courses for the training of specialists but these are elective except in two or three cases.  相似文献   

6.
Cryptosporidium is an important protozoan that cause diarrheal illness in humans and animals. Different species of Cryptosporidium have been reported and it is believed that species characteristics are an important factor to be considered in strategic planning for control. We therefore analyzed oocysts from human and animal isolates of Cryptosporidium by PCR-RFLP to determine strain variation in Isfahan. In total, 642 human fecal samples from children under five years of age, immunocompromised patients, and high risk persons and 480 randomly selected rectal specimens of cows and calves in Isfahan were examined. Microscopic examination showed that 4.7% (30/642) of human samples and 6.2% (30/480) of animal samples were infected with Cryptosporidium. After identification of the samples infected with the parasite, oocysts were purified and their DNA was extracted. We used PCR-RFLP analysis of a 1750-bp region of 18S rRNA gene to identify Cryptosporidium species. The human samples were infected with Cryptosporidium parvum II, C. muris, C. wrairi, and a new genotype of Cryptosporidium (GenBank accession numbers: DQ520951). The cattle samples were identified as C. parvum II, C. muris, C. wrairi, C. serpentis, C. baileyi, and a new genotype of Cryptosporidium (GenBank accession numbers: DQ520952). Also we found a new genotype infecting both human and cattle samples (GenBank accession numbers: DQ520950). In addition to demonstrating the widespread occurrence of most species of Cryptosporidium, C. parvum, we also observed extensive polymorphism within species. Furthermore, the occurrence of the same species of parasite in both animal and human samples shows the importance of the animal-human cycle.  相似文献   

7.
The aims of this study were to explore the use of animals in teaching and the implementation of innovative technology-based teaching practices across a small sample of universities in Eastern Europe. The research methods used were a questionnaire circulated four weeks before a workshop took place (in October 2009, in Belgrade, Serbia), as well as focused, face-to-face group discussions, led by one of the authors during the workshop. Twenty-two faculty (physiologists and pharmacologists), from 13 Eastern European countries, attended the meeting. Fourteen of the eighteen schools represented at the workshop were making use of animals, in some instances in quite large numbers, for their teaching. For example, a single department at a Romanian university used over 250 animals per annum, and at least 1130 animals were used, per annum, across all of the institutions. The species used in largest numbers were the rat (34%), frog/toad (29%), mouse (22%), rabbit (10%), guinea-pig (4%) and dog (1%). None of the universities sampled had implemented institution-wide virtual learning environments (VLEs), although there were isolated instances of local use of VLEs. There was relatively little current use of technology-based teaching and learning resources, but there was considerable enthusiasm to modernise teaching and to introduce innovative learning and teaching methods. The major perceived barrier to the introduction of replacement alternatives was the lack of versions in local languages. There was a consensus view that developing local language exemplars and evaluating their usefulness was likely to have the greatest impact on animal use, at least in the short-term.  相似文献   

8.
In an experiment to investigate the effect of the tick parasitoid, Ixodiphagus hookeri, on tick numbers on cattle, 150 000 parasitoids were released over a period of 1 year in a field where ten cattle infested with multiple tick species were kept. Amblyomma variegatum was reduced from 44 to two ticks per animal while Rhipicephalus appendiculatus increased over the time of parasitoid release. During the time of release 51% of the nymphs of A. variegatum collected from the animals were parasitized. The recovery of the parasitoids after the releases were stopped was only 9%. The total numbers of A. variegatum remained low up to 1 year after the parasitoid release was stopped. This study gives an insight into how I. hookeri could be used strategically for the management of A. variegatum on small-scale farms.  相似文献   

9.
本研究以常用于动物种属鉴定的12S rRNA基因位点为研究对象,利用所测得的17种常见涉案兽类12S rRNA基因部分片段序列及NCBI数据库中下载的该物种DNA序列及其近缘物种DNA序列,构建系统进化树。根据进化树的聚类情况,判断NCBI数据库中的相关基因序列或物种名称的正确性,并对其中错误序列的登陆号进行标记,以防对后续涉案动物的准确鉴定造成影响。分别从17种常见涉案兽类(共26份样本)中提取线粒体DNA,并利用通用引物扩增线粒体DNA上的12S rRNA基因部分片段并进行测序分析。通过NCBI数据库的Blast比对功能,筛选出与本研究物种同源性由高到低的物种,并从NCBI基因数据库中下载此类近缘物种的12S rRNA基因序列共351条,利用MEGA7.0软件构建该物种及其近缘物种系统进化树。通过比对发现NCBI中登录号为KP202279等3个序列所对应物种拉丁名错误。登录号为AY184436等11个序列所对应物种拉丁名可能存在疑问。GenBank中某些物种拉丁名有同种异名现象。因此,NCBI数据库数据可靠性有待进一步验证,只能作为涉案物种鉴定的参考数据之一,可借助构建系统进化树等方法来确认其结果的准确性。  相似文献   

10.
Beach surveys for harp (Phoca groenlandica) and hooded (Cystophora cristata) seals documented a dramatic increase in their numbers on Sable Island in the mid-1990s. From late 1994 to 1998, 1,191 harp and 870 hooded seals, mostly young animals, were recorded on the island whereas, in the 1980s, no more than 5 animals of both species were observed each year. Of the 2,061 harp and hooded seals examined, 41.7% were found alive, 26.7% were killed by sharks, and 31.6% were found dead but intact. This increase in numbers of harp and hooded seals on Sable Island, which is south of their historic northern range, is consistent with the recent increase of extralimital occurrences of these species along the east coast of North America. However, the large number of seals recorded in this study provides more information on their demography than has previously been possible.  相似文献   

11.
Aim  In this study, a dataset on world-wide squirrel introductions has been used to locate the relative pathways and to determine the factors correlated with species establishment.
Location  The world.
Methods  The analysis includes a chronological table of introductions, a biogeographical analysis and an assessment of the likelihood of establishment according to species, propagule pressure, area of origin and characteristics of the recipient area.
Results  The main vector of such introductions was the intentional importation of live animals. Introductions increased in developed countries and proportionately to the volume of imported mammals. Moreover, areas characterized by higher numbers of native squirrels were more invaded. Squirrels were often introduced deliberately and only to a smaller extent escaped from captivity. The likelihood of their establishment increased proportionately to the number of animals released and decreased proportionately to the increase of the latitudinal distance between the recipient area and the native range of the species. The likelihood that the release of one pair of either Sciurus or Callosciurus species would establish a new population was higher than 50%.
Main conclusion  Squirrels proved to be successful invaders and their importation should be restricted so as to prevent further introductions.  相似文献   

12.
Keeping and breeding Dall's Sheep (Ovis dalli) in Leipzig Zoo between 1982 and 2009 are reflected and analysed. Seven animals were brought into the collection. 60 specimens were kept so far. The species hast turned out to be difficult in Middle-Europe‘s climate but nevertheless is manageable and reproductive. The rearing rate (animals have reached at least the age of 1 year) is 40%. Remarkable veterinarian treatments for keeping the stock healthy and especially for ensuring the breeding are described. For sure, deep engagement of keepers, veterinarians and curators is needed to keep this species successfully. Hopefully a lot of colleagues will take this as a challenge to increase numbers in Europe by joining the group of holders of this splendid wild sheep.  相似文献   

13.
In many parts of the world, millions of wildlife species are hunted for sport, food, skins, and other products. In recent years, a backlash has emerged from certain groups of society against this long-standing human pursuit. However, attitudes towards the control of wild animals to reduce the health risk to other animals, to lessen agricultural damage, or to protect game species, may generate a different reaction, where even killing is tolerated. In this paper, we analyze the public’s acceptance of control hunting in Andalusia (southern Spain). Our results suggest that lethal control to improve domestic animal health is highly accepted (75%) is more controversial when animals are killed for damaging crops (59% acceptance) and is highly unaccepted when the goal is to enhance game species numbers (22% acceptance). Older people and males, in particular, accept more readily some of these control-hunting measures. These results are needed to understand better the public attitudes on which conservation managers can base their decisions when control hunting is required.  相似文献   

14.
Evidence exists, particularly in the welfare literature of nonhuman animals on the farm, that the interaction between nonhuman animals and the personnel who care for them can have a strong effect on the animals' behavior, productivity, and welfare. Among species commonly used for biomedical research, mice appear to be the least-preferred species in animal care facilities. A review of the literature and observations of animal care staff interacting with mice indicated that the following factors may influence this: their small size, their particular behavioral characteristics, and husbandry constraints (such as housing in ventilated racks). In addition, this study questioned whether animal care personnel have a different perception of genetically engineered animals and whether this, in turn, has an effect on their interactions with these animals. The ability to carefully observe an animal's behavior is key in carrying out an animal-wellness assessment and in minimizing pain and distress. Attention to human-animal interactions in the research setting represents an opportunity for refinement for large numbers of animals and potentially for reduction of animal use.  相似文献   

15.
Evidence exists, particularly in the welfare literature of nonhuman animals on the farm, that the interaction between nonhuman animals and the personnel who care for them can have a strong effect on the animals' behavior, productivity, and welfare. Among species commonly used for biomedical research, mice appear to be the least-preferred species in animal care facilities. A review of the literature and observations of animal care staff interacting with mice indicated that the following factors may influence this: their small size, their particular behavioral characteristics, and husbandry constraints (such as housing in ventilated racks). In addition, this study questioned whether animal care personnel have a different perception of genetically engineered animals and whether this, in turn, has an effect on their interactions with these animals. The ability to carefully observe an animal's behavior is key in carrying out an animal-wellness assessment and in minimizing pain and distress. Attention to human-animal interactions in the research setting represents an opportunity for refinement for large numbers of animals and potentially for reduction of animal use.  相似文献   

16.
Rescue centres in the Czech Republic care for injured, young uninjured, and otherwise physically damaged wild animals that are temporarily or permanently incapable of looking after themselves without assistance or incapable of surviving in the wild. We evaluated the numbers of mammals admitted to 37 rescue centres in the Czech Republic in a ten year period from 2011 to 2020, the causes leading to the admission of these mammals to rescue centres, their outcomes and their length of stay at rescue centres. In total, 73,499 mammals were admitted to the Czech rescue centres in the monitored period, with an increasing trend being found in the number of admissions (rSp = 0.9030, p < 0.05). The mammals admitted in the largest numbers were Chiroptera (39.36%), primarily the common pipistrelle (Pipistrellus pipistrellus), and Insectivora (35.85%), of which the largest proportion was made up of European hedgehogs (Erinaceus europaeus). Although according to the IUCN classification only 0.26% of admitted animals belonged among Endangered or Critically Endangered species, according to the Czech legislation, 47.21% of admitted mammals belonged to species in varying degrees of endangerment in this area. The most frequent reasons for admission were the admission of young (33.18%) with differences between the Orders - the highest number of admitted young of Rodentia (72.66% of all admitted Rodentia) and the lowest number of young of Chiroptera (2.74%). Of all mammals admitted to rescue centres, 45.83% were released back into the wild, 24.52% died at rescue centres, and 9.50% were euthanized. The highest release rate was achieved in Chiroptera (74.60%) especially those that suffered from malnutrition (63.09% of all admitted Chiroptera due to malnutrition). The length of stay was longest in young Artiodactyla released back to the wild (median 87 days). The data obtained from rescue centres provide an overview of the numbers and species of animals admitted and the outcome of their rehabilitation. Since almost half of mammals admitted could not be returned to the wild, it is also important to determine correctly which individuals should be treated and what is the most efficient use of resources for wildlife rehabilitation.  相似文献   

17.
Birds’ nests may be refuges for various species of fungi including that which are potentially phytopathogenic and zoopathogenic. Among the 2449 isolates of fungi obtained from nests of Marsh harriers 96.8% belonged to filamentous fungi. In total, 37 genera were identified from 63 fungi species. Within the mycobiotas of the examined nests populations of fungi which are potentially pathogenic for humans, homoiothermous animals and plants dominated. Among 63 species, 46 (72%) were potentially pathogenic fungi of which 18 species were potentially phytopathogenic and 32 species were pathogenic for homoiothermous animals. Inter alia species of fungi were found in the Marsh harriers nests: Aspergillus fumigatus, Aspergillus flavus, Scopulariopsis brevicaulis, Chrysosporium keratinophilum and Fusarium poae, Fusarium sporotrichioides. In terms of numbers, dominant in Marsh harrier nests were fungi pathogenic to birds, other homoiothermous animals and humans. On that basis it was concluded that Marsh harrier nests are both a source of fungal infections for that species and one of the links in the epidemiological cycle of opportunistic fungi for humans.  相似文献   

18.
Re-introductions are increasingly used conservation tools. Often, criteria for re-introducing species are based on policies or politics and little attention paid, albeit theoretical, to understanding what ecological possibilities habitats may have in sustaining introduced animals. Assessing potential carrying capacities is complex but easier for grazers, since biomass of these herbivores is empirically correlated with habitat primary productivity.The case is made here that the Barbary macaque, Macaca sylvanus, a vulnerable North African primate with a large surplus captive stock, can be viewed as a grazer. Because of this attribute, and unlike congenerics, it is possible to estimate potential densities in extant habitats in a fashion similar to predicting stocking levels for domestic herbivores. Thus, from values of consumable primary productivity for domestic stock in Mediterranean countries and the monkey's energy requirements, attainable macaque populations in studied habitats could be much higher than actual. Though these numbers may be unreachable in nature, this study shows that present macaque populations could increase after restorative management of habitats in which re-stocking with captive-born animals may play a part. However, since only 10% of potential monkey habitat in Morocco and Algeria is occupied by the species, finding areas for releasing captive-born macaques is more advisable.  相似文献   

19.
Zoonoses     
Yamada A 《Uirusu》2004,54(1):17-22
The numbers of microbial species that can infect human beings are shown to be 1415, of which 868 species (61%) are zoonotic. Since most of the emerging pathogens (75%) are originated from other animals, public health sectors should be vigilant against the emergence of new zoonotic diseases. Only 33% of zoonoses can spread from human to human after introduction into human population. Various factors such as human demography, ecological change, global transportation and climate change are responsible for the emergence of zoonoses. Even a slight change in the ecological niche where pathogenic organisms thrive would result in the increase of the incidence of the disease.  相似文献   

20.
Thirty adult donkeys from Burkina Faso were necropsied and their gastro-intestinal worm burdens counted and determined. The strongylids were the most abundant species with a prevalence of 100% for Strongylus vulgaris. Four species of Strongylus, two of Triodontophorus and six of the Cyathostominae were recovered. All of the animals were also infested with habronematid nematodes, but oxyurid and ascaridid nematodes were found in low numbers. In addition to the nematodes, the paramphistomid trematode Gastrodiscus aegyptiacus and the anoplocephalid cestode Anoplocephala magna occurred in varying numbers. Faecal egg-counts from 131 donkeys ranged between 100 and 9,200 for strongylid eggs.  相似文献   

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